A number of improvements have been made in the booster seat art in recent years. Early booster seats had a fixed seat and, therefore, were not adjustable for either the size of the child or a preferred seating orientation. Generally, such seats were designed only for use as a booster seat. More recently, improvements have been made in the field which have made the seats adjustable not only in seat height, but also reclinable so that they may accommodate very small children as well as to accommodate the preferred feeding position of a maturing child, and they have been made more versatile by providing them with trays which enable the booster seats to function as feeding chairs.
U.S. Pat. No. 4,854,638 shows such a booster seat wherein the back rest and seat panel may be moved back and forth, and up and down respectively, and the assembly includes a detachable tray. Another booster seat found in the prior art has an invertible seat panel which allows the seating surface to be raised or lowered depending upon which seating surface is utilized. That arrangement is shown in U.S. Pat. No. 4,586,747. Other prior art patents that show children's seats that are collapsible, such as U.S. Pat. Nos. 1,739,366 and 4,603,903, while other adjustable child's seats are shown in U.S. Pat. Nos. D330,842 and D314,674.
U.S. Pat. No. 6,033,019 and U.S. Pat. No. D424,312 disclose a tiltable seat for holding a child and a removable feeding tray. A back portion of the seat is joined to a bottom portion, which is supported on a base, and the seat has a number of selectable height adjustment positions relative to the back portion of the seat. A series of selectable tilt positions are also provided for the back and seat portion relative to the base. The feeding tray is adapted to be removably attached to both of the side arms of the seat frame and tilts in angular orientation cooperatively with the arms of the seat to which it is attached. This arrangement is an issue, because of the limited adjustment mechanism between the seat and the feeding tray. While in and out adjustment of the feeding tray, relative to the seat back, can be accomplished, it is difficult if not impossible to maintain the tray in a flat, horizontal orientation relative to the ground as the seat tilts. Although the base includes a pair of spaced apart slots for receiving a strap to secure the seat to a support, such as a chair, this seat is not easily transported since the seat comes apart in several large pieces, which are not foldable, and thus difficult to transport and store.
Similarly, published U.S. Patent Application No. 2003/0151285 A1 discloses a seat which tilts on top of a base and which is also height adjustable relative thereto. The removable tray, which is adjustable in and out relative to the seat via a number of fixed notches in the seat, is provided with only one pair of notches that permits angular adjustment of the tray relative to the seat and thus, in many instances, the tray cannot be aligned horizontal or flat relative to the ground. Again, this seat is bulky, difficult to transport and severely limited in tray adjustment capabilities.